Tuesday, March 8, 2011

The vanishing browns

Circa 1984 (IISc Platinum Jubilee publication)

Open habitat and bare ground is perhaps something that humans do not like. If one looks over the plains of India, (courtesy of an ATR 72) there is a striking pattern - black roads stretch over brown and yellow-green lands and where the vein-like roads meet are patches of dark profuse tree growth. Where more roads meet, these green patches are larger. The similarity to the roots of a gigantic tree or a fungal colony on a Petri dish is striking. The roots of trees or fungal mycelia help gather and centralize nutrients. A faculty member at my university used to emphasise this movement of nutrients from the countryside through agricultural produce to get discarded in the cities thereby becoming nutrient sinks. These nutrients then enrich the vegetation within the cities.

Grass and scrub (1986, own photo)
Looking west from the northeastern edge. The two tall Araucaria trees
were favourite perches for a pair of visiting Red-necked Falcon.
These grasslands were home to jackal and hare as well.
Harriers, Black-winged Kite, Kestrels and Rollers were regulars here.

Looking back at an aerial photograph of the Indian Institute of Science (IISc) from 1984 tempted me to try out the new Google Earth. The latest version has a nice history time line allowing one to see changes in cover over time. I could not help noticing the same phenomenon of human spread causing the intensification of green cover. After spending about twelve years watching birds in the campus of the Indian Institute of Science and noting the changes, it appeared then that the birds most at risk were those of open land. In those times, the northern end of IISc with its gravelly airstrip was bordered by low grass, scrub and open land. This held breeding populations of White-throated Munia, Yellow-wattled Lapwings, Pied Bushchat, Indian Robin, Red-wattled Lapwing, Plain Prinia, Jerdon's Bushlark, Paddyfield Pipit, Indian Nightjar and Ashy-crowned Sparrow-Lark. Bordering the swimming pool where CEDT stands today was a low marshland where Baya Weaver and Tricoloured Munia could be found. While swimming in the afternoon, one just had to look up to see the occassional Painted Storks soaring above or the Brahminy Kite that nested on the Eucalyptus adjoining the pool. The bare ground below the famous union-jack Ficus benjamina grove opposite the central office was the usual haunt of hoopoes. This was also a coppersmith hotspot. The wetland was filled up later the water draining to the Sankey Tank. The open lands got used for buildings and trees cover took over rapidly. The open land is now either built up or covered in trees and is now devoid of lapwings, larks, robins and nightjars.

Increasing green cover in campus in 2007 (Google Earth)

By 1988, the Common Iora had already been declared as locally extinct on the campus. It was however regularly seen at the Lalbagh botanical gardens and at the UAS campuses at Hebbal and GKVK. By 2000, even these places lost their Iora populations. It was said that Large-grey Babblers were found on the IISc campus in the 1960s (according to Prof. K.K. Neelakantan's notes seen by Dr S. Subramanya). In the late 1980s, the nearest locations for them were in the south near the Valley School. I have early memories of Indian Robins that ran on the sand driveway at the entrance of the Guest House although in the 1990s they were restricted along the northern boundary wall. These too are now no longer present, and gone also are the Plain Prinias.

Brown to green - 2010 (Google Earth)

According to BirdLife International (1994) grassland and desert birds make up 6.3 and 9.3 percent respectively of all threatened birds. That includes things like bustards, florican, cranes, coursers and others (perhaps several waders from the steppe and tundra as well).

IISc grassland (looking towards CPRI) around 1990

When habitats change, some birds leave and other birds turn up. Around 1996-97, the White-browed Bulbul, formerly absent on campus occupied habitats adjoining the Jubilee Park. In 2011, some participants of a competitive birding event photographed an Orange-breasted Green Pigeon! On a chance visit to the NIAS campus which now stands where the Yellow-wattled Lapwings nested, I saw Black-naped Orioles (and it seems to have become a regular winter visitor by 2012). In recent times there have also been cases of the Indian Grey Hornbill, another large frugivore, turning up in Lalbagh. It would demonstrate some knowledge if it was possible to predict what will go next and what would take their place as habitats change inside our campuses and cities. With the Indian Institute of Science taking over a new campus in Chitradurga, it seems like they have a clean slate to work on! Hopefully, they will use their scientific training in managing their landuse this time round.

Postscript
5-Jan-2015 - The British Library has an interesting old map of Bangalore and here is how IISc aligns over it. A single tongue of water draining into Sankey tank still exists, running in front of the old CES building, beside the Sadashivanagar police station. A remnant of the long tongue that turns around Yeshwanthpur runs as ditch along the southern wall of Kendriya Vidyalaya IISc (we ran inside it as kids!).